AMD Radeon Instinct MI25 vs NVIDIA GeForce RTX 4080 Comparison

AMD Radeon Instinct MI25 and NVIDIA GeForce RTX 4080 occupy very different positions in the database, separated by five years of architecture evolution and distinct design goals. The single head-to-head benchmark available, Geekbench OpenCL, shows a decisive victory for the RTX 4080, but the story is richer than a single score. The MI25 is a compute-focused accelerator from 2017, while the RTX 4080 is a consumer flagship from 2022, and their specifications reflect those divergent paths.

Where Each One Wins

The data presents a clear split in purpose. The AMD Radeon Instinct MI25 wins in the context of its legacy compute role, being an end-of-life product from the Radeon Instinct generation. Its strengths lie in its specific memory configuration and its place in the database’s historical record, not in raw contemporary performance. The MI25’s benchmark score of 68,562 in Geekbench OpenCL places it at the 90th percentile among all GPUs, which is respectable for a 2017-era accelerator.

The NVIDIA GeForce RTX 4080 wins decisively in the only direct comparison available. Its Geekbench OpenCL score of 214,739 is 68.1% higher than the MI25’s score, a massive margin that reflects the generational leap. The RTX 4080 also holds an 86th percentile ranking among all GPUs, slightly lower than the MI25’s 90th percentile, but this is because the database includes many more modern, high-performance cards in its full ranking. The RTX 4080’s wins extend across a broader benchmark suite, including 3DMark Steel Nomad DX12, multiple Passmark tests, and Vulkan workloads, where it demonstrates versatility that the MI25, with only a single recorded OpenCL score, cannot match.

The use-case split is straightforward: the MI25 was designed for data center compute tasks of its era, while the RTX 4080 is built for gaming and general-purpose compute with modern API support. The MI25 has no display outputs, confirming its role as a headless compute accelerator. The RTX 4080 includes HDMI and DisplayPort outputs, making it suitable for interactive workloads.

Architecture Differences

The architectural gap between these two GPUs is substantial. The MI25 uses the Vega 10 chip built on the GCN 5.0 architecture, manufactured on a 14 nm process at GlobalFoundries. This is a mature, power-hungry design from the mid-2010s. The RTX 4080 uses the AD103 chip based on Ada Lovelace, built on a 5 nm process at TSMC, representing a fundamental shift in transistor density and efficiency.

The transistor counts tell the story. The MI25 packs 12,500 million transistors on a 495 mm² die, yielding a density of 25.3 million transistors per square millimeter. The RTX 4080 crams 45,900 million transistors onto a smaller 379 mm² die, achieving 121.1 million transistors per square millimeter. That is nearly five times the density, enabled by the newer process node. The RTX 4080 also introduces dedicated ray tracing cores (76 of them) and tensor cores (304 of them), features entirely absent from the MI25, which relies solely on its 4,096 shading units.

Memory architecture differs fundamentally. The MI25 uses 16 GB of HBM2 with a 2048-bit bus, delivering 436.2 GB/s of bandwidth. The RTX 4080 also has 16 GB, but uses GDDR6X on a 256-bit bus, achieving 716.8 GB/s. The HBM2 approach on the MI25 offers a wider bus but lower clock speeds, while the RTX 4080’s GDDR6X runs at 22.4 Gbps effective, far exceeding the MI25’s 1704 Mbps effective memory speed. The MI25’s memory clock is listed at 852 MHz, while the RTX 4080’s is 1400 MHz.

Compute capabilities diverge sharply. The MI25 delivers 12.29 TFLOPS FP32 and 24.58 TFLOPS FP16 with a 2:1 ratio. The RTX 4080 delivers 48.74 TFLOPS FP32 and 48.74 TFLOPS FP16 with a 1:1 ratio, meaning it does not halve its throughput for half-precision work. This is a critical difference for AI and compute workloads that rely on FP16.

Head-to-Head Benchmarks

The only direct benchmark in the database is Geekbench OpenCL, and it is a landslide. The NVIDIA GeForce RTX 4080 scores 214,739, while the AMD Radeon Instinct MI25 scores 68,562. That is a delta of -68.1%, meaning the MI25 achieves less than one-third of the RTX 4080’s score. The margin is so large that it overshadows any other comparison.

Looking at the RTX 4080’s broader benchmark suite adds context. It scores 6,567 in 3DMark Steel Nomad DX12, 263,779 in Geekbench Vulkan, and 34,457 in Passmark G3D. It also records 20,671 in Passmark GPU Compute. These results indicate strong performance across different rendering APIs and compute workloads. The MI25 has no comparable scores in the database, limiting the ability to assess its performance beyond the single OpenCL test.

The RTX 4080’s nearest rivals in the database are instructive. It sits just 0.1% ahead of the RTX 4080 SUPER, 1.1% behind the AMD Radeon Pro W5700X, 2.6% behind the AMD Radeon RX 6750 GRE 12 GB, and 2.7% behind the AMD Radeon 8060S. These are close margins, suggesting the RTX 4080 is finely positioned among its contemporaries. The MI25’s rivals, by contrast, include the Intel Arc A770 (-0.4%), NVIDIA CMP 90HX (-0.6%), AMD Radeon Pro WX 8200 (-1.9%), and NVIDIA Quadro P6000 (-2%), all of which are within 2% of its score. This shows the MI25 was competitive within its 2017-era class, but that class is now far behind modern parts.

FAQ

Q: Which GPU has a higher Geekbench OpenCL score?

A: The NVIDIA GeForce RTX 4080 scores 214,739, which is 68.1% higher than the AMD Radeon Instinct MI25’s 68,562.

Q: Are both GPUs the same memory size?

A: Yes, both have 16 GB of memory, but the MI25 uses HBM2 with a 2048-bit bus, while the RTX 4080 uses GDDR6X with a 256-bit bus.

Q: Which GPU has ray tracing support?

A: Only the NVIDIA GeForce RTX 4080 has ray tracing cores, specifically 76 of them. The AMD Radeon Instinct MI25 has no ray tracing cores listed.

Q: What is the transistor density difference?

A: The RTX 4080 has a transistor density of 121.1 million per mm², while the MI25 has 25.3 million per mm², a nearly fivefold difference.

Q: Does the MI25 have any display outputs?

A: No, the AMD Radeon Instinct MI25 has no display outputs, while the RTX 4080 includes 1x HDMI 2.1 and 3x DisplayPort 1.4a.

Q: How do their FP16 compute rates compare?

A: The RTX 4080 delivers 48.74 TFLOPS FP16 with a 1:1 ratio, while the MI25 delivers 24.58 TFLOPS FP16 with a 2:1 ratio, meaning the RTX 4080 is roughly double in raw FP16 throughput.

The Verdict

The data is unambiguous: for any modern compute or graphics workload, the NVIDIA GeForce RTX 4080 is the superior choice. It outperforms the MI25 by 68.1% in the only shared benchmark, offers ray tracing and tensor cores, has higher memory bandwidth, and supports newer APIs including DirectX 12 Ultimate and Vulkan 1.4. The RTX 4080’s FP32 throughput of 48.74 TFLOPS is nearly four times the MI25’s 12.29 TFLOPS. Anyone selecting between these two for current tasks should choose the RTX 4080 without hesitation.

The AMD Radeon Instinct MI25 remains relevant only for legacy compute deployments or as a historical data point. Its 90th percentile ranking is respectable, but that ranking is against all GPUs in the database, including many older ones. Its 12.29 TFLOPS FP32 and 436.2 GB/s bandwidth were adequate for 2017 data center workloads, but they are far below the RTX 4080’s capabilities. The MI25’s lack of display outputs and reliance on GCN 5.0 architecture further limit its appeal outside specialized compute roles.

For users with specific legacy software that was optimized for GCN architecture, the MI25 could still function, but the database provides no evidence of any workload where it beats the RTX 4080. The verdict is clear: the RTX 4080 wins on every measurable metric, and the MI25 is a product of its time, best left to historical analysis.

Specification Differences

The specifications differ across nearly every category. The process node is 14 nm for the MI25 versus 5 nm for the RTX 4080. Transistor count is 12,500 million versus 45,900 million. Die size is 495 mm² versus 379 mm². Base clock is 1400 MHz versus 2205 MHz. Boost clock is 1500 MHz versus 2505 MHz. Memory clock is 852 MHz (1704 Mbps effective) versus 1400 MHz (22.4 Gbps effective). Memory bandwidth is 436.2 GB/s versus 716.8 GB/s. Shading units are 4,096 versus 9,728. TMUs are 256 versus 304. ROPs are 64 versus 112. The RTX 4080 adds 76 ray tracing cores and 304 tensor cores, which the MI25 lacks entirely. Pixel rate is 96.00 GPixel/s versus 280.6 GPixel/s. Texture rate is 384.0 GTexel/s versus 761.5 GTexel/s. FP32 is 12.29 TFLOPS versus 48.74 TFLOPS. FP16 is 24.58 TFLOPS (2:1) versus 48.74 TFLOPS (1:1). TDP is 300 W versus 320 W. Slot width is dual-slot versus triple-slot. Power connectors are 2x 8-pin versus 1x 16-pin. Bus interface is PCIe 3.0 x16 versus PCIe 4.0 x16. Display outputs are none versus 1x HDMI 2.1 and 3x DisplayPort 1.4a. DirectX support is 12 (12_1) versus 12 Ultimate (12_2). Vulkan support is 1.3 versus 1.4. Dimensions are 267 mm length and 111 mm height versus 310 mm length, 140 mm height, and 61 mm width. Release dates are 2017-06-26 versus 2022-09-19. The RTX 4080 has a launch MSRP of 1,199 USD. The MI25 has no recorded launch MSRP.